Trig: Law of Cosines & Law of Sines (Song)

This silly math song teaches the Law of Cosines and the Law of Sines. In Trigonometry (generally taught as part of PreCalculus) these laws are both used when solving triangles.

YouTube Video

Song explains the notion of solving triangles, and how sides and angles are labeled. It teaches the Law of Cosines (Cosine Law) and shows how to remember it using the Pythagorean Theorem as a reference. It explains that it is appropriate to use the Law of Cosines when you know the lengths of all three sides of a triangle (SSS), or if you know the lengths of two sides of a triangle plus the measure of one angle (SAS, SSA). Finally, it teaches the Law of Sines (Sine Law) and explains that it is appropriate to use it when you know the measure of two angles of a triangle plus the length of one side (AAS, ASA), or if you know the lenth of two sides of a triangle plus the measure of an angle that is not between these two sides (SSA). The song includes an explanation of the SSA case, and why there are generally two different triangles possible when SSA is given. The song is sung/rapped to the tune of "Party Rock Anthem" by LMFAO.